Biomedical subjects

Paolo Tosoni

Publications and source records attributed to Paolo Tosoni.

4 recordsLinked to original sources

PubMed2004

Relation between leptin and the metabolic syndrome in elderly women.

BACKGROUND: Leptin has been shown to be linked to adiposity and insulin resistance in middle-aged participants. However, the association between leptin and metabolic syndrome independently of body fat and body fat distribution has not been evaluated in healthy elderly people. METHODS: We studied the independent relation between leptin and the components of the metabolic syndrome in 107 women aged 67-78 years with body mass index (BMI) ranging from 18.19 to 36.16 kg/m2. In all participants, we evaluated BMI, waist and hip circumferences, body composition by dual energy X-ray absorptiometry, fasting, and 2-hour glucose, lipids, insulin, homeostasis model assessment of insulin resistance (HOMA), systolic (SBP), diastolic blood pressure (DBP), and leptin. RESULTS: Significant correlation was found between leptin, BMI, waist circumference, fat mass, DBP, SBP, cholesterol, triglycerides, insulin, and HOMA. After adjusting for age and waist circumference, as well for age and fat mass, leptin was significantly related to insulin levels, HOMA, and cholesterol. In a stepwise multiple regression analysis using insulin levels or HOMA as dependent variables and age, waist circumference, fat mass, leptin, SBP, DBP, cholesterol, and triglycerides as independent variables, leptin entered the regression first, waist circumference second, and age third. CONCLUSION: Our study shows that leptin is significantly related to indices of adiposity in elderly women, and leptin is significantly associated with insulin levels, HOMA, and cholesterol independent of age, body fat, and fat distribution. Leptin, waist circumference, and age together explained 31% and 33% of insulin levels and HOMA variance, respectively, in healthy elderly women.

Age Factors↗

PubMed2003

Body composition changes in stable-weight elderly subjects: the effect of sex.

BACKGROUND AND AIMS: Although cross-sectional and longitudinal studies have shown age-related changes in body composition and fat distribution, they may be related to body weight changes. The aim of this study was to evaluate yearly age-related changes in body composition and fat distribution, over a two-year period, in 101 women and 60 men (age range: 68 to 78 years at baseline). METHODS: Body composition was evaluated by dual energy X-ray absorptiometry (DXA), and fat distribution by waist and hip circumferences and waist-to-hip circumference ratio. Baseline free testosterone, IGF-1 and serum albumin were evaluated in all subjects, as well as physical activity. Clinical evaluation was performed at baseline and yearly in order to exclude subjects with any condition inducing pathological changes in body composition or fat distribution. Subjects with a weight change > 5% of their baseline body weight during the study period, were excluded. RESULTS: Significant increases occurred in Body Mass Index (BMI) (1.18% in women, 1.13% in men), waist (1.75% in women, 1.39% in men), and hip circumference (1.06% in women, 1.31% in men), whereas height decreased significantly in both men (0.42%) and women (0.55%). Significant increases in total body fat (1.31%) and percent body fat (1.27%) were observed in women but not in men. Lean body mass did not change significantly throughout the study in either sex. Significant losses in leg muscle mass and appendicular skeletal muscle mass (ASM), calculated as the sum of arm and leg fat-free soft tissue, were observed in men (respectively 3.56 and 2.77%) and women (respectively 2.41 and 1.59%). A significant decrease in ASM adjusted by stature (ASM/height2), a proposed proxy for sarcopenia, was found in men only (1.97%). The rates of loss in leg muscle mass and appendicular muscle mass were significantly higher in men than in women, even after adjusting for free testosterone, IGF-1, physical activity and serum albumin. CONCLUSIONS: These data demonstrate significant changes in body composition and fat distribution in independently living, weight-stable elderly men and women. These changes are dependent on sex and independent of physical activity, hormones or serum albumin.

Absorptiometry, Photon↗

PubMed2003

Relationship between leptin levels and bone mineral density in the elderly.

OBJECTIVE: To assess the relationship between circulating leptin levels, bone mineral content and density in the elderly. DESIGN: A cross-sectional study. PATIENTS: A cohort of 92 men and 171 women, with ages ranging from 68 to 75 years, selected as a healthy and normal functioning group, in the city centre of Verona. MEASUREMENTS: Plasma leptin levels were determined in each participant. Body composition was evaluated with dual energy X-ray absorptiometry (DXA). Bone mineral content (BMC) and bone mineral density (BMD) were measured at whole-body, hip and femoral neck level in all subjects. RESULTS: In both men and women a significant relationship between fat mass and whole-body BMC or BMD was found. The strength of this association was consistently reduced after adjustment for plasma leptin. A significant association between circulating leptin levels, whole-body, total hip and femoral neck BMC and BMD was found in both sexes. This association retained the statistical significance after adjustment for fat mass percentage, especially in women. In stepwise multiple linear regression analyses, leptin was shown to be a significant predictor of whole-body, total hip and femoral neck BMC and BMD, independently of age and the percentage of body fat in both sexes. The circulating levels of leptin accounted for a variance in whole-body BMC of 8.9% in men and 18.2% in women, and in whole-body BMD of 10.6% in women. CONCLUSION: Our data show a significant relationship between leptin, bone mineral mass and density in healthy elderly men and women.

Absorptiometry, Photon↗

PubMed2002

Relation between vitamin D, physical performance, and disability in elderly persons.

BACKGROUND: The aim of this study was to evaluate the relationships between vitamin D, functional status, and disability in a sample of elderly, community-dwelling subjects. METHODS: Serum values of 25-hydroxyvitamin D (25[OH] D) and albumin were determined in all participants. Anthropometric measures were obtained, and body composition was assessed using dual-energy x-ray absorptiometry. Arm and leg isometric strength was tested. Reported disability was evaluated using a modified version of the Activities of Daily Living Scale and physical performance with the 6-minute walking test and two items of the Short Form 36 Health Survey Questionnaire (SF-36). RESULTS: A significantly higher prevalence of hypovitaminosis D, defined as level of 25(OH)D < 37.5 nmol/l, was observed in women than in men (55.4% and 35.1%, respectively; p <.001). In women, 25(OH)D was significantly associated with muscular strength and levels of physical function as assessed by SF-36. After adjusting for body mass index, albumin, appendicular fat-free mass, and season, muscle strength was still significantly lower in women with hypovitaminosis D than in those without. Women with reported disability showed significantly lower 25(OH)D values than those without. No relationship between muscular strength, physical function, or reported disability and 25(OH)D was found in men. CONCLUSIONS: In community-dwelling elderly women, 25(OH)D is related to muscular function and reported disability. Because of the high prevalence of hypovitaminosis D in the elderly population, this association seems to be clinically relevant.

Aged↗